MOSCOW - Riot police hauled away dozens of protesters and at least two opposition leaders on Sunday after scuffles broke out at a demonstration against Vladimir Putin's return to Russia's presidency, witnesses said.

A long line of OMON riot police held back protesters at a square across the Moscow river from the Kremlin and beat some with batons. Some of the protesters threw plastic bottles and one threw a smoke bomb, Reuters reporters on the scene said.

Those taken away by police included two opposition leaders, Alexei Navalny and Sergei Udaltsov, the witnesses said.